861225753042 has 18 divisors (see below), whose sum is σ = 1865997662373. Its totient is φ = 287073938592.

The previous prime is 861225753029. The next prime is 861225753131. The reversal of 861225753042 is 240357522168.

861225753042 is a `hidden beast` number, since 8 + 6 + 1 + 2 + 2 + 575 + 30 + 42 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 779920363161 + 81305389881 = 883131^2 + 285141^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=656211.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3827898 + ... + 4046634.

Almost surely, 2^861225753042 is an apocalyptic number.

861225753042 is an abundant number, since it is smaller than the sum of its proper divisors (1004771909331).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861225753042 is an frugal number, since it uses more digits than its factorization.

861225753042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437482 (or 218742 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 45.

The spelling of 861225753042 in words is "eight hundred sixty-one billion, two hundred twenty-five million, seven hundred fifty-three thousand, forty-two".